The Wallingford office building that houses some operations for Anthem Blue Cross and Blue Shield and other commercial tenants is in special receivership while its owner works out a plan for repaying the balance of a $26.4 million mortgage, a New York loan tracker says.

The owner of Campus At Greenhill, a two-story, 287,967-square-foot Class A edifice at 100 Leigus Road, adjacent to I-91, is one month behind, as of Sept. 1, on the outstanding $24.5 million balance of a loan-refinancing that Swiss financier UBS issued in 2011, according to loan data compiled by Trepp LLC.

The 104-acre property was valued at $34.4 million in 2014, Trepp said.

Anthem Health is the six-year-old building's lead tenant, occupying some three-quarters of the space under a lease that expires in 2022, Trepp data shows.

Kansas City, Mo., engineering firm Burns & McDonnell's Northeast regional headquarters occupies 27,635 square feet, or about 12 percent, of Greenhill's space in a lease that ends in 2019. According to the Campus at Greenhill, homepage, Burns & McDonnell was underway with a 6,719-square-foot expansion to its office footprint.

In 2013, the engineering firm's existing Greenhill space was awarded LEED gold from the U.S. Green Building Council's Leadership in Energy & Environmental Design program for its sustainable site development, water savings, energy efficiency, and indoor environmental quality.

Prospectus footnotes for the loan, Trepp said, indicate that Anthem had the right to terminate about 67,000 square feet last Aug. 1. Burns & McDonnell also has a termination option. Both options required advance notice as well as a termination fee.

Spokesmen for Anthem and Burns & McDonnell did not immediately respond to requests for comment.

Greenhill's common areas include a cafeteria, fitness center and showers, according to the property's homepage. Originally designed and built by Workstage-Connecticut LLC, Gale Development acquired the property in 2010 and completed it in 2011.

The Greenhill loan accounts for less than 2 percent of the outstanding collateral that anchors a much larger securitized pool of mortgages, Trepp said.

The note has been on the servicer watchlist for the last two months as a result of the borrower not submitting 2016 financials within the required time frame, according to Trepp. Special servicer comments released this month offered no specifics for the transfer.